Egyptian authorities arrested dozens of people on Monday in connection with clashes against police in Alexandria over the weekend, according to the state-run MENA news agency.

Protesters and police came to blows outside the Alexandria courthouse on Sunday after a panel of judges decided not to deliver a much-anticipated verdict in cases against police officers accused of killing protesters during the 2011 revolution.

The ruling enraged families of the victims and protesters who had gathered outside the courthouse to hear the verdict, said Ahmed Mamdouh, a lawyer representing families of several of the victims.

There are conflicting accounts of the clashes.

Mamdouh claims that police were the aggressors, accusing them of attacking families of the victims.

The spokesman for the Interior Ministry, Alaa Mahmoud, told CNN that none of the protesters was injured in the fighting, but seven police officers suffered various injuries.

Protesters set fire to two police cars and broke into the courthouse and torched documents inside the archive department, MENA reported.

More than 800 people died during the uprising that toppled the government of Hosni Mubarak in 2011. Many of the police officials charged in the killing have been acquitted because of a lack of evidence.

The escalating tension in Alexandria comes just days before the two-year anniversary of the 2011 revolution on January 25.

Several opposition groups have called for mass protests in Cairo on Friday to mark the anniversary and to protest against President Mohamed Morsy and what they call his failure to bring about positive change and uphold the principles of the revolution.